Warm-Up  What human process uses the most water on the planet?  How can farmers save water?

Greenhouse Effect  Water vapor and carbon dioxide – major greenhouse gases Trap heat in our atmosphere  Without the greenhouse gases, Earth would be too cold to live on

Greenhouse Effect  Humans can impact the greenhouse effect Burning of fossil fuels releases CO 2 into the atmosphere Increasing the amount of carbon dioxide which causes temperatures to increase beyond the normal amounts

Global Warming  Global warming – increase in global temperatures from an increase in carbon dioxide ○ Might lead to the melting of the glaciers ○ Would raise sea level 60 meters and would flood coastal towns

Global Warming  Global Warming could potentially have an affect on the biosphere Glaciers melt  Destroys polar bears habitats Sea level rises

Measuring Global Warming  Temperatures in the Northern Hemisphere from 200 A.D. – 2000 A.D.  At the start of the Industrial Revolution – temperatures began to rise and have continued

Measuring Global Warming  Arguments that skeptics of global warming put forth: Before humans the Earth went through climate shifts There is not enough evidence 2009-Global warming activists knowingly submitted false data to forward their agenda